Method to adhere thermoplastic elastomer blends to polyester substrates

Abstract

A method to adhere thermoplastic elastomer blends comprising (a) at least one thermoplastic polyolefin, (b) at least one non-cured, partially cured or fully cured elastomer or blends thereof, (c) a functionalized polyolefin and (d) optionally additives, to a polyester substrate, said method comprising the steps of treating the substrate with a blocked di-isocyanate in aqueous dispersion, or subsequently or simultaneously treating the substrate with a blocked di-isocyanate and an epoxy resin in aqueous dispersion/emulsion, applying the thermoplastic elastomer blend to the treated substrate and bonding the thermoplastic elastomer blend to the surface of the substrate using heat and pressure. The invention further relates to shaped articles obtainable by said process.

I claim: 
     
       1. A method for adhering thermoplastic elastomer blends to a polyester substrate, said method comprising the steps of: (A) treating the polyester substrate with a blocked di-isocyanate in aqueous dispersion and an epoxy resin in aqueous emulsion,   (B) applying to the treated polyester substrate a thermoplastic elastomer blend comprising (a) at least one thermoplastic polyolefin,   (b) at least one elastomer which has been at least partially cured by dynamic vulcanization in the presence of (a),   (c) a functionalized polyolefin, and   (d) optionally additives, then     (C) bonding the thermoplastic elastomer blend to the polyester substrate at a temperature between about 170° C. and about 280° C. and at a pressure between about 0.1 MPa (1 bar) and about 20 MPa (200 bar).   
     
     
       2. The method of claim 1 wherein the polyester substrate is treated with blocked di-isocyanate prior to, simultaneously with, or after treatment with epoxy resin. 
     
     
       3. The method of claim 1, wherein the thermoplastic elastomer blend comprises about 10% to about 87% by weight of the at least one thermoplastic polyolefin (a),   about 10% to about 70% by weight of the at least one elastomer (b),   about 3% to about 80% by weight of the functionalized polyolefin (c), and   up to about 65% by weight of additives (d), with the proviso that the amount of (a)+(b)+(c) is at least 35% by weight, based on the total amount of (a)+(b)+(c)+(d).   
     
     
       4. The method according to any one of claims 1 or 3 wherein in the thermoplastic elastomer blend comprises (a) least one thermoplastic polyolefin selected from a homopolymer or copolymer of a C 2-7  monoolefin monomer or a copolymer thereof with (meth)acrylates and/or vinyl acetates, and   (b) at least one elastomer selected from the group consisting of EPDM rubber, EPM rubber, butyl rubber, halogenated butyl rubber, copolymers of isomonoolefin and para-alkylstyrene or their halogenated derivatives, natural or synthetic rubber, polyisoprene polybutadiene rubber, styrene-butadiene-copolymer rubbers, nitrile rubbers, polychloroprene rubbers and mixtures thereof.   
     
     
       5. The method according to any one of claims 3 to 4 wherein the functionalized polyolefin is selected from homopolymers or copolymers of C 2  -C 7  monoolefin monomers or copolymers thereof with (meth)acrylates or vinyl acetates having grafted thereon monomers selected from unsaturated carboxylic acids containing 3 to 20 carbon atoms, dicarboxylic acids containing 4 to 10 carbon atoms or their derivatives or their anhydrides provided that they exist, epoxy-group containing esters of unsaturated carboxylic acids containing at least 6 carbon atoms, hydroxy-group containing esters of unsaturated carboxylic acids containing at least 5 carbon atoms, oxazolines, said unsaturated carboxylic acid or unsaturated dicarboxylic acid monomers being furtiler functionalized with polyamines, and mixtures thereof. 
     
     
       6. The method according to any one of claims 1 or 3-5 wherein the content of the graft monomers is between about 0.3% by weight and about 10% by weight, based on the amount of the functionalized polyolefin (c). 
     
     
       7. The method according to any one of claims 1 or 3-6 wherein the amount of functionalized polyolefin (c) in the thermoplastic elastomer blend is between about 5% by weight and about 75% by weight, based on the amount of the thermoplastic elastomer blend. 
     
     
       8. The method according to claim 1 wherein the substrate is selected from a polyester which is optionally epoxy activated. 
     
     
       9. The method according to any one of claims 1 or 3-8 wherein the blocked di-isocyanates are selected from caprolactam blocked methylene-bis-(4-phenylisocyanate or 4,4'-methylene-bis-(phenylcarbanilate). 
     
     
       10. The method according to claim 9 wherein the amount of blocked di-isocyanate or blocked di-isocyanate and epoxy resin on the substrate is from about 5 to about 500 grams per m 2  of substrate surface. 
     
     
       11. The method according to any one of claims 1 or 3-10 wherein the epoxy resins are selected from glycerol-polyglycidylether or the reaction-product of bisphenol A and epichlorohydrin. 
     
     
       12. A shaped article comprising a substrate and a thermoplastic elastomer adhering to the surface or part of the surface of said substrate, said shaped article being obtainable by the method as defined in any one of claims 1, 3-11 or 2. 
     
     
       13. The shaped article according to claim 13 wherein the substrate is selected from a polyester fiber, polyester cord and polyester fabric.